Make a vinaigrette by whisking together:
-1 shallot, finely minced
-small bit of dijon mustard
-glug of good-quality (i.e., sweet and tart, not sour) balsamic vinegar
-glug of extra-virgin olive oil
-a tablespoon of chopped herbs (I used thyme, sage, and rosemary)
-good salt and freshly ground pepper
Adjust the vinaigrette to taste. If you have a not-so-sweet balsamic, you could add a small bit of honey if you like. If you have a super-sweet one, relatively more mustard or a dribble of red wine vinegar will balance the sweetness. You can keep this in the fridge for a few days, and really it gets better as the flavors meld together.
Cook some smallish pasta, such as orzo, and combine it with some of the vinaigrette, plenty of crumbled feta cheese, and halved cherry tomatoes. Adjust the proportions by taste—you should be able to just taste the herbs and the shallots, and it should be pleasantly tangy&sweet&salty. Eat right away or pack for lunch.
(Other things that I didn't have on hand but that I suspect might go well here: chopped kalamata olives, small broccoli florets slightly steamed, chopped roasted red peppers, etc.)